1. Field of the Invention
The present invention relates to electrical generators and, more specifically, to electrical generators employing piezoelectric nanostructures.
2. Description of the Related Art
As an abundant energy in our daily life, mechanical energy ranges from sonic waves, mechanical vibration and impacts, air flow (e.g., wind), friction, hydraulic and ocean waves, which are available around the clock. Harvesting mechanical energy and converting it into electrical energy is becoming an increasingly important alternative to conventional electrical generation methods.
Piezoelectric zinc oxide (ZnO) nanowires (nanowires) have been used for harvesting small-scale mechanical energy created by a gentle physical motion. Using a single ZnO nanowire, an alternating-current (AC) generator has been demonstrated based on cyclic stretching and releasing of a piezoelectric fine-wire.
The design of a single nanowire based AC-NG uses a piezoelectric wire that is firmly contacted at its two ends with metal electrodes, laterally bonded and packaged on a flexible substrate, the bending of which can be driven by mechanical agitation present in our living environment. The single wire generator demonstrates a robust approach for harvesting low-frequency energy generated by in-vitro human or animal motion. However, the output power of a single nanowire based nanogenerator (NG) may be limited. In certain practical applications, it is essential to scale up the design of the AC-NGs so as to integrate the contributions made by millions of nanowires in order to enhance the output power.
Most current systems are not sufficiently scalable to enable them to generate power for many applications.
Therefore, there is a need for large scale nanogenerator arrays.